This is an RAC Application for Continuation of an approved and funded grant, HLB 13595, for study of mechanisms participating in the pathogenesis of hypertension. Current studies that will be continued or expanded are: a. Evaluation of mechanisms in clinical and experimental hypertension due to glucocorticoid excess. b. Assessment of the role of vasopressin (AVP) in experimental renoprival hypertension and renal insufficiency. c. Analysis of activation of the renin-angiotensin system in acute pancreatitis. d. Study of the response of plasma catecholamines and plasma renin activity to dynamic exercise in age-matched normal subjects and mild uncomplicated hypertensive patients.